Fluid pump



July 25, 1950 B. P. POND ETAL 2,516,589

FLUID PUMP Filed Jan. 10, 1947 2 Sheets-Sheet 1 III 1120517075: Ber-7E1: J? Pond j 64 Edwin 1622;11-

M41759; EDeLar-mg M a W flW y 5, 1950 B. P. POND ETAL 2,516,589

FLUID PUMP Filed Jan. 10, 1947 2 Sheets-Sheet 2 Barf-E52 .F? Pond Edwin E. Vz'rzcerz'l' War/e12 HDeLmcgy Patented July 25, 1950 FLUID PUMP Bertram P. Pond, Longmeadow, and Edwin E.

Vincent and Warren H. De Lancey, Springfield,

Masa, assignors to Engineering Products, Inc., Springfield, Mass a corporation of Massachuse Application January 10, 1947, Serial No. 721,227

This invention relates to an improved pumping unit, and more particularly to a pumping unit which is designed for use in oil burners.

It is the primary object of the present invention to provide a pumpingunit which will be most economical to manufacture but which at the same time will be constructed in a manner such that it may function most efiiciently.

A further object of the present invention is to provide a pump unit which will have its component parts so disposed that they may be readily disassembled and reassembled thereby to facilitate the inspection and repair thereof.

With the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts, hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention from which the several features of the invention and the advantages attained thereby will readily be understood by those skilled in the art.

In the accompanying drawings:

Fig. 1 represents a longitudinal sectional view of the present pumping unit.

Fig. 2 is an enlarged sectional view of the valve unit taken substantially along the line 2-2 of Fig. 1.

Fig. 3 is a sectional view through the forward portion of the pumping unit taken substantially along the line 3-3 of Fig. 1.

Fig. 4 represents a sectional view taken substantially along the line 4-4 of Fig. 1.

Fig. 5 represents a sectional view taken substantially along the line 5-5 of Fig. 1.

Fig. 6 represents a sectional view taken substantially along line 6-6 of Fig. 1.

Referring particularly to Fig. 1, the present pumping unit broadly comprises a substantially cylindrical casing in having a hollow front chamber it formed in the forward portion thereof, which chamber isadapted to be completely enclosed by means of an end cap 12 removably secured to the casing by means of a plurality of bolts l3. Communicating with the chamber II is a bore it which extends into a rear chamber l5 which in turn opens out upon the rear end portion of the casing ill to be covered by means of a rear end cap l6 which is removably secured to the casing by means of a plurality of-bolts ll. Force fitted into the bore I4 is a hollow sleeve bushing I8 in which is rotatably mounted a driving shaft IS the distal end portion of which extends through an aperture provided in the end cap it. An electric motor, or any other suitable prime mover, may be coupled to the dis- 1 Claim. (01. 103-126) tal and of the shaft IQ for the purpose of rotating the same thereby to actuate the pumping unit. The rearward endof the sleeve i8 is provided with an angular flange 2! which abuts against a rear wall 22 of the -chamber l5 and the forward end of this sleeve projects into the chamber H and has a back plate 23 of the pumping unit positioned thereabout. Abutting against this back plate 23 within the chamber i is an annular ring' 24 which forms a spacer unit for the pump proper and abutting against this spacer ring is the front plate 25 of the pumping unit.

The two plates 23 and 25 and thespacer ring 24 are all adapted to be secured together by means of a plurality of bolts 26 which are threaded directly into the rear wall portion of the chamber It.

In order to prevent the shaft 19 from moving endwise within the sleeve l8 an intermediate portion of the shaft has mounted thereon a sealing and thrusting ring 27 the front portion of which abuts against the flange 2! of the sleeve l8 and has an oil slot 21' formed therein. The element 27 cooperates with an annular ring 28 in preventing endwise movements of the shaft and the ring 28 is carried upon the forward end of the shaft l9 and is held thereon by means of a snap ring 29 which may be seated in an annular groove 29' formed on the extreme forward portion of the shaft l9. It is to be understood that the ring 28 abuts against a recessed face 30 of the front plate 25 of the pumping unit.

Referring particularly to Figs. 1 and 3, there is removably positioned in the chamber Ii an oil filter unit comprising a wire screen 3i which is formed substantially into a hollow cylindrical unit which is closed at its ends by means of a forward plate 32and a rear plate 33. The rear plate 33 is provided with an apertured flanged portion 34 which is adapted to be inserted directly within the recess 30 of the front plate 25 of the pumping unit. It is to be understood that this filter unit, comprising the screen 3| and the front and back plates 32 and 33, may be readily inserted into .and removed from the chamber II by merely removing the forward cap from the casing l0. Referring particularly to Fig. l, the front cap l2 has its rear face recessed as at 36 thereby to provide a seat for a coil spring 3'! which is adapted to bias the filter unit inwardly so that the flange 34 forcibly engages the edge portions of the recess 30. From the above, it is to be understood that whenever the end cap I 2 is removed from the easing 10 the filter unit may be removed from the chamber it without disturbing an of the elements of the pumping unit. This is an important feature of the present device as it permits the filter to be removed and cleaned by unskilled persons.

Referring particularly to Figs. 1 and 5, the

present pumping unit is adapted to receive oil from a supply source. not shown herein, and

which oil may gain entrance into the pumping unit through a bore 54 provided within the raised portion 35 of the casing It. An entrance oil line may be secured to either end of the bore 35 while the other end of the bore may be provided with a plug. The oil from the supply source once directed into the bore 35 will find its way into the hollow chamber Ii and about the filter screen ll through which it will penetrate thus to gain entrance into the filter unit from which it may be then directed into the pumping unit proper.

Referring particularly to Figs. 1, 3, and 4, the recessed face 30 of the front plate 25 is provided with an aperture 45 which is adapted to lead the oil from the inside portion of the filter unit to an arcuately shaped recess 4| provided on the inside face of the plate 25. Referring to Figs. 1 and 5,

the oil which gains entrance into the groove 4| will be led directly into a low pressure'side of the pumping unit proper which comprises a gear 42 which is mounted directly upon a crowned portion 43 of the shaft it. A key 44 projecting inwardly from the gear engages the shaft i! thereby to permit the gear 42 to be driven directly by the shaft. Surrounding the gear 42 is a complementary internal gear 45 which is mounted within an aperture 46 eccentrically provided within the spacer ring t4. As may be seen particularly in Fig. 5, the gear 42 meshes with the internal gear 45 at a point 41 thereby to provide low pressure spaces 48 at the left hand side of the gear and high pressure spaces 49 on the right hand side of the gear. As the shaft i9 rotates in a clockwise direction, as viewed in Fig. 5, the coacting gears 42 and 45 will create a low pressure within the spaces 45 thereby to draw the oil, provided from the above noted source of supply, into the spaces 48 and to force the same into the spaces 45 from which the oil is directed into an arcuate groove 55, provided in the back face of the forward plate 25 and into an arcuate groove provided in the forward face of the back plate 23 (see Figs. 4 and 6). This all which gains entrance under pressure into the arcuate grooves 50 and 5! is then forced into a conduit 52 which communicates with the groove 5| and which extends through the back plate 23 to open into a circular recess 53 provided in the rear face of a back plate 28. From this recess 53 the oil, still under pressure, is directed into a longitudinal bore 54 (see Fig. 1) which communicates directly with a second bore 55 which, along with bore 54, is provided in the back wall of the chamber i I. From the above it is to be understood that the pumping unit is adapted to create a low pressure area to which oil from a source of supply is drawn, which oil is passed through the filter unit before gaining entrance into the pumping unit proper. Once within the pumping unit proper, the oil is forced under pressure from the pumping unit and shaft it is to be desired that this oil should be led back into the pump proper rather than having 4 it spill out along the distal end of the shaft II. In order to accomplish this purpose there is provided within the chamber I5 of the casing II a bellows type sealing unit which comprises a plate 55 which is secured directly between the rear portion of the casing I0 and the rear end cap 15 as at 51. Spaced from the plate 55 and about the shaft is is ring 58 connected to the plate 55 by means of cylindrical bellows 55. A coil spring 5', positioned between the ring 58 and the plate 55, functions to bias the ring 55 directly against the ring 21 for the purpose of forming a seal between the rotating ring 21 and the stationary plate 55. The oil which escapes from the pump along the shaft I! will enter into the chamber l5 and about the bellows 59 by way of the slot il formed in the ring 21. This oil in chamber l5 will. then enter into a longitudinal bore 8| formed in the casing adjacent the sleeve it. This bore 6| is in communication with an aperture 82 provided in the back plate 23 of the pump unit which aperture i2 is directed through the plate 23 to open directly within an arcuate slot 53 provided in the forward face of the back plate 23 and disposed in registration with the arcuate slot 4| provided in the rear face of the forward plate 25. Thus, this slot 63 will be positioned adjacent the low pressure areas 48 and, therefore, it will be effective to permit the pumping unit to scavenge the oil from the chamber i5 of the casing Iii. This oil will, of course, be recirculated into the system and will finally be directed under pressure into the bore 55.

The above noted valve mechanism of the pres ent device functions as an oil discharge control mechanism to the end that oil cannot be ejected from the pumping unit until or unless the oil reaches a predetermined pressure. Therefore, whenever the pumping unit is first started this valve mechanism is effective to prevent any oil discharge until the pump speed is sufficient to produce a predetermined pressure in the oil. Also this valve will function to cut oh. the ejection of oil from the pump whenever the pump slows down preparatory to stopping for when the pump slows down it cannot produce a proper pressure of the oil.

Referring particularly to Figs. 1 and 2, this valve unit is provided within a casing protuberance 64 in which is formed a central bore 65 terminating in enlarged and bores 66 and 61. Fixed within the bore 65 is a hollow cylinder 68 in which is slidingly received a piston member 59 having a head member 10. the head member 10 is a longitudinal aperture Ii into which is slidingly mounted a needle valve 12 which is surrounded with a coil spring 13 for the purpose of providing a substantially floating mounting for the valve 12. The one end of this spring 13 engages a flange portion 14 of the valve and the other end portion of the spring 13 engages a washer 15 which is held within the head It by means of a snap ring it. Thus the valve 12 is held within the head It as a floating element.

Threaded within the bore 66 is a discharge nut 11 having an aperture 18 formed centrally thereof into which is secured a valve seat 15 having a discharge orifice formed axially thereof. This orifice 80 communicates directly with a threaded aperture 8| which is adapted to be connected directly with an oil burner unit. Positioned between the nut 1'] and a flange 8-2, formed on the cylinder 68, is a coil spring 83 the function of which is to secure the sleeve 58 in its proper position at all times.

Formed within 7 Threaded into the bore is an adjusting nut 84 which has threaded longitudinally therein an adjusting screw 85 the inner end portion of which has mounted thereon a cap 86 against which one end of a coil spring 81 abuts. The other end of this coil spring 8! projects into the piston 68 to engage the head portion 18 thereof for the purthe oil under pressure from the pumping unit to the bore 66 and about the needle valve 12. It is to be understood that whenever the pressure of this oil reaches a predetermined magnitude it will be sufllcient to force the piston 69 against the spring 81 to the end that the valve 12 will be backed away from the valve seat I8 thereby to permit the oil to be ejected through the orifice 80 and to an oil burner unit. By adjusting the screw 85 one may have the valve 12 operate at any given predetermined oil pressure.

Formed in the wall of the cylinder 68, adjacent its flange 82 are a plurality of circumferentially spaced apertures 90 which communicate with the bore 66 and which normally have their inner ends closed off by the piston 69. However, whenever the piston is forced inwardly within the cylinder 68 the apertures 90 will then be placed in register with a plurality of apertures 8i formed within and about the periphery of the piston 69. Whenever the conduits 90 and 9| are thus in register, the oil under pressure will be directed into the hollow portion of the piston 68 from which it will flow through an opening 92' which leads directly into a bore 93 formed within the protuberance 64 (see Figs. 2 and 4). Referring particularly to Fig. 4, one end portion of the bore 93 opens directly within a, chamber ll thus to return the oil back into the pumping system. The lower end of the bore 93 is threaded as at 94 for the purpose of receiving a plug, or if desired a return pipe the other end of which will be connected to the oil supply tank. Thus, it is to be understood that the present pumping unit is adapted to supply oil in excess to the valve orifice 80 and whenever the pressure of this oil is great enough to open the needle valve 12 a portion of this oil will be ejected through the orifice 88 while the remaining oil will be directed back into the pumpin system by means of conduits 80 and 8| and the bore 83.

Referring particularly to Figs. 2 and 4, there is provided within the protuberance 84 a second bore 95 which communicates with the bore 66 by means of an opening 96. This bore 85 will receive the high pressure oil directly from the bore 66 and it may have secured to its threaded portion, as at 91, a pressure gage if such is desired, otherwise, a plug may be threaded into the bore 95 thereby to close off the same.

From the above description it is apparent that the present pumping unit is designed to be manufactured at a low cost for the reason'that the entire unit is made up of a plurality of lesser units which may be assembled together by persons having little or no mechanical skill. Furthermore, the present pump design is such that relatively unskilled persons may readily disas-v semble and assemble this unit for the purpose of inspecting and replacing the various component parts thereof. It is to be understood that the unit broadly comprises a casing it having formed therein a pair of spaced chambers H and" which are connected by means of a bore H. In order to assemble the various parts of the unit it is only necessary to insert the shaft l9, having the ring 21 thereon, into the rear chamber l5, place the pumping elements over the forward end of the shaft, and then tighten the bolts 26 in place and position the ring 28 and snap 28 over the shaft and against the plate 25. Thus, the main elements of the pump require no elaborate tools for the assembly thereof. The remaining elements of the pump proper, including the oil sealing units and the filter element, may thus be slipped into position and locked within the casing by merely bolting home the two end caps.

The assembly method of the valve mechanism is substantially the same as that of the pump unit for the reason that the removal of the two nuts 11 and 84 of the valve unit will expose all of the internal valve mechanism which may be hand assembled and disassembled in place.

-We claim:

In a device of the character described having a unitary casing with a front and a rear chamber each formed centrally within a respective one of the opposite end portions thereof, an interior wall portion of said casing separating said two chambers and having a central bore formed therein for connecting said two chambers, an end cap removably secured over each of said chambers, a rotary pump disposed within said front chamber and against said interior wall portion, a fluid delivery conduit formed in said casing and communicating with said front chamber for delivering fluid to said rotary pump, and a fluid discharge conduit disposed within said interior wall portion for conducting fluid under pressure from said pump; the combination therewith of a a shaft rotatably mounted within said bore and extending into each of said chambers, one end of said shaft extending through that end cap which covers said rear chamber and the other end being operatively connected with said pump, a fluid seal surrounding said shaft and disposed within said rear chamber adjacent the end cap thereof so as to prevent escape of fluid from said rear chamber past said rear end cap, a thrust ring formed intermediate the ends of said shaft and disposed within said rear chamber so as to prevent endwise movement of said shaft in a, first direction, means in the form of a split ring carried upon one end of said shaft and engaging said pump so as to prevent endwise motion of said shaft in a second direction, a spiral groove formed about said shaft and connecting said rear chamher with the high pressure side of said pump so as to provide high-pressure lubrication of said shaft, and a conduit formed within said interior wall portion and connecting said rear chamber with the low pressure side of said pump so as to draw the lubricating fluid from said rear chamber, to relieve said fluid seal from pressure of said fluid.

BERTRAM. P. Porfi). EDWIN E. VINCENT. WARREN H. DE LANCEY.

(References on following page) 7 nmnmcns mm H I Th'e'tollowmg references are 0! record in the 111: 01 this patent: 233g I UNITED STATES PATENTS 5 Number Name Date 2.248 308 1,271,910 Wood ....0 July 9. 19.1: 1,379,587 Fisher May 24,1221 1,927,749 Kimmlz Sept. 19, 1933 Number Doe: July 0, 1040 10 0 Name Date Huber Aug. 27, 1940 Wahlmark Feb. 25, 1941 Osborne Mar. 4, 1941 Wahlmark Feb. 2, 1943 Bohr --Apr. 11, 1944 FOREIGN PATENTS Country Datc' France 1924 

